diff --git a/configure.ac b/configure.ac
index 4fc06330adb855d074591cd8fbf09d2b4d2b745d..41420556f1b077701a747589df37ef7d596473ce 100644
--- a/configure.ac
+++ b/configure.ac
@@ -3,7 +3,7 @@ dnl Process this file with autoconf to produce a configure script.
 dnl graph-tool package version number
 m4_define(graph_tool_version_major, 2)
 m4_define(graph_tool_version_minor, 2)
-m4_define(graph_tool_version_micro, 21)
+m4_define(graph_tool_version_micro, 22dev)
 
 AC_INIT([graph-tool],[graph_tool_version_major().graph_tool_version_minor().graph_tool_version_micro()],[http://graph-tool.skewed.de])